Passenger conveyors such as escalators and moving walks typically have a frame that supports a passenger moving portion upon which passengers are situated and a drive for causing the moving portion to travel along the frame. The moving portion has a series of steps for the case of an escalator and a flat platform for the case of a moving walk. A pair of balustrades having handrails, skirt panels and balustrade panels is attached to the frame and is substantially vertically disposed on either side of the moving portion.
The skirt panel extends along and adjacent the moving portion, for example escalator steps, and extends vertically upward from the treads of the steps. The skirt panel is generally stationary while the escalator steps are in motion. The skirt panel and moving escalator steps are separated by a skirt/step gap that is usually 1/16 inch or more, but may be smaller.
Passenger injuries have occurred by entrapment in the skirt/step gap of objects such as body parts, clothing or accessories. Body parts that have been entrapped include limbs, fingers, feet, toes, hair and the like. Clothing that has been entrapped includes shoes, shoe laces, draw strings, scarves and the like. Accessories that have been entrapped include pocket books, book bags, back packs and the like.
Entrapment occurs as a result of the moving object coming in contact with the stationary skirt panel, being slowed or stopped by the frictional force of the contact and then being forced into the skirt/step gap as the escalator steps continue to move. Entrapment can occur at any point along the skirt/step gap. Any point where entrapment occurs, is known as the pinch point. For example, one point of the skirt/step gap where many entrapments occur is the juncture of the tread of one step and the riser of the next step. Some known skirt panels have deflected away from the moving steps upon heavy contact so that the skirt/step gap and pinch point becomes enlarged, thereby enhancing the chance of an entrapment
The entrapment problem has been addressed in several ways. U.S. Pat. No. 5,695,040 discloses an escalator that has a brush or a wiper disposed in the skirt/step gap as a blocking member. Both the brush and the wiper are flexible so that objects that enter the skirt/step gap are still subject to seizure and entrapment.
A side-of-step entrapment product, available under the SafetyStrip.TM. trademark from Adams Elevator Company of Niles, Ill. is a continuous brush that is installed along the length of the skirt panel. The brush is supposed to warn passengers of impending danger when they or their clothing contact it and to present a barrier that must be penetrated to reach the skirt/step gap. This may work for some passengers, but not all. There are some passengers whose limbs (for example, their feet) will miss the brush and contact the skirt panel and be forced into the skirt/step gap. Other passengers will bump hard into the brush, penetrate the brush barrier and contact the skirt panel so as to be exposed to entrapment in the skirt/step gap. Some items of clothing may miss the brush and become entrapped. Other items of clothing that contact the brush may still contact the skirt panel and become entrapped.
Another technique has been to coat the skirt panel with a low friction material having a low coefficient of friction (lower than that of stainless steel). However, the materials used have not reduced friction enough to overcome the entrapment problem.
An escalator step guidance system, available under the SureGuide.TM. trademark from Schindler Elevator Corp. of Morristown, N.J. reduces the skirt/step gap size by means of a screw and wiper pad assembly that is mounted below each step tread. Whether the skirt/step gap is 1/16 inch, larger or smaller, there is a skirt/step gap in which objects may be entrapped.